1. Field of the Invention
The present invention relates to a semiconductor light-emitting element, and particularly to a semiconductor light-emitting element of which light extraction efficiency is enhanced and to a manufacturing method of the semiconductor light-emitting element.
2. Description of the Related Art
In a semiconductor light-emitting element composed of semiconductor materials, a refractive index of an inside of the semiconductor light-emitting element is higher than a refractive index of the air to which light is finally emitted. Therefore, the light generated in a pn junction in the inside of the semiconductor light-emitting element is reflected owing to a refractive index difference on an interface between the air and the semiconductor materials, and the light cannot be sufficiently extracted to an outside of the semiconductor light-emitting element.
As a countermeasure against this problem, it has been proposed to stack a transparent material having a refractive index that is intermediate between the refractive index of the semiconductor materials and refractive indices of sealing resin and the air on a light extraction surface of the semiconductor light-emitting element. Moreover, it has been proposed to increase light extraction area/solid angle by performing a process such as surface roughening for the light extraction surface, and such a proposal has been put into practical use.
However, even by means of these methods, efficient extraction and maximum use of the light generated in the inside of the semiconductor light-emitting element have not been achieved yet.